Yes there are grills at the campsites and they have a waterpark but the lake I would not swim in.
The only swimming at the park is at the beach area on the south side of the park and when you fall off the ski risen. Grills yes in the campsites. Each site has it's own grill.
There is a water park there but you have to pay to get in and maybe not much room for extensive swimming.
Yes about grilling yes about swimming if your not afraid of gators
There is an area where one can fake water-ski and it looks like some of the water "rope-pull" lake sports so there must be swimming.
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